<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Usage | Node.js v8.12.0 Documentation</title>
  <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Lato:400,700,400italic">
  <link rel="stylesheet" href="assets/style.css">
  <link rel="stylesheet" href="assets/sh.css">
  <link rel="canonical" href="https://nodejs.org/api/synopsis.html">
</head>
<body class="alt apidoc" id="api-section-synopsis">
  <div id="content" class="clearfix">
    <div id="column2" class="interior">
      <div id="intro" class="interior">
        <a href="/" title="Go back to the home page">
          Node.js
        </a>
      </div>
      <ul>
<li><a class="nav-documentation" href="documentation.html">About these Docs</a></li>
<li><a class="nav-synopsis active" href="synopsis.html">Usage &amp; Example</a></li>
</ul>
<div class="line"></div>

<ul>
<li><a class="nav-assert" href="assert.html">Assertion Testing</a></li>
<li><a class="nav-async_hooks" href="async_hooks.html">Async Hooks</a></li>
<li><a class="nav-buffer" href="buffer.html">Buffer</a></li>
<li><a class="nav-addons" href="addons.html">C++ Addons</a></li>
<li><a class="nav-n-api" href="n-api.html">C/C++ Addons - N-API</a></li>
<li><a class="nav-child_process" href="child_process.html">Child Processes</a></li>
<li><a class="nav-cluster" href="cluster.html">Cluster</a></li>
<li><a class="nav-cli" href="cli.html">Command Line Options</a></li>
<li><a class="nav-console" href="console.html">Console</a></li>
<li><a class="nav-crypto" href="crypto.html">Crypto</a></li>
<li><a class="nav-debugger" href="debugger.html">Debugger</a></li>
<li><a class="nav-deprecations" href="deprecations.html">Deprecated APIs</a></li>
<li><a class="nav-dns" href="dns.html">DNS</a></li>
<li><a class="nav-domain" href="domain.html">Domain</a></li>
<li><a class="nav-esm" href="esm.html">ECMAScript Modules</a></li>
<li><a class="nav-errors" href="errors.html">Errors</a></li>
<li><a class="nav-events" href="events.html">Events</a></li>
<li><a class="nav-fs" href="fs.html">File System</a></li>
<li><a class="nav-globals" href="globals.html">Globals</a></li>
<li><a class="nav-http" href="http.html">HTTP</a></li>
<li><a class="nav-http2" href="http2.html">HTTP/2</a></li>
<li><a class="nav-https" href="https.html">HTTPS</a></li>
<li><a class="nav-inspector" href="inspector.html">Inspector</a></li>
<li><a class="nav-intl" href="intl.html">Internationalization</a></li>
<li><a class="nav-modules" href="modules.html">Modules</a></li>
<li><a class="nav-net" href="net.html">Net</a></li>
<li><a class="nav-os" href="os.html">OS</a></li>
<li><a class="nav-path" href="path.html">Path</a></li>
<li><a class="nav-perf_hooks" href="perf_hooks.html">Performance Hooks</a></li>
<li><a class="nav-process" href="process.html">Process</a></li>
<li><a class="nav-punycode" href="punycode.html">Punycode</a></li>
<li><a class="nav-querystring" href="querystring.html">Query Strings</a></li>
<li><a class="nav-readline" href="readline.html">Readline</a></li>
<li><a class="nav-repl" href="repl.html">REPL</a></li>
<li><a class="nav-stream" href="stream.html">Stream</a></li>
<li><a class="nav-string_decoder" href="string_decoder.html">String Decoder</a></li>
<li><a class="nav-timers" href="timers.html">Timers</a></li>
<li><a class="nav-tls" href="tls.html">TLS/SSL</a></li>
<li><a class="nav-tracing" href="tracing.html">Tracing</a></li>
<li><a class="nav-tty" href="tty.html">TTY</a></li>
<li><a class="nav-dgram" href="dgram.html">UDP/Datagram</a></li>
<li><a class="nav-url" href="url.html">URL</a></li>
<li><a class="nav-util" href="util.html">Utilities</a></li>
<li><a class="nav-v8" href="v8.html">V8</a></li>
<li><a class="nav-vm" href="vm.html">VM</a></li>
<li><a class="nav-zlib" href="zlib.html">ZLIB</a></li>
</ul>
<div class="line"></div>

<ul>
<li><a class="nav-https-github-com-nodejs-node" href="https://github.com/nodejs/node">GitHub Repo &amp; Issue Tracker</a></li>
<li><a class="nav-https-groups-google-com-group-nodejs" href="https://groups.google.com/group/nodejs">Mailing List</a></li>
</ul>

    </div>

    <div id="column1" data-id="synopsis" class="interior">
      <header>
        <h1>Node.js v8.12.0 Documentation</h1>
        <div id="gtoc">
          <ul>
            <li>
              <a href="index.html" name="toc">Index</a>
            </li>
            <li>
              <a href="all.html">View on single page</a>
            </li>
            <li>
              <a href="synopsis.json">View as JSON</a>
            </li>
            
    <li class="version-picker">
      <a href="#">View another version <span>&#x25bc;</span></a>
      <ol class="version-picker"><li><a href="https://nodejs.org/docs/latest-v9.x/api/synopsis.html">9.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v8.x/api/synopsis.html">8.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v7.x/api/synopsis.html">7.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v6.x/api/synopsis.html">6.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v5.x/api/synopsis.html">5.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v4.x/api/synopsis.html">4.x <b>LTS</b></a></li>
<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/synopsis.html">0.12.x</a></li>
<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/synopsis.html">0.10.x</a></li></ol>
    </li>
  
          </ul>
        </div>
        <hr>
      </header>

      <div id="toc">
        <h2>Table of Contents</h2>
        <ul>
<li><span class="stability_undefined"><a href="#synopsis_usage">Usage</a></span><ul>
<li><span class="stability_undefined"><a href="#synopsis_example">Example</a></span></li>
</ul>
</li>
</ul>

      </div>

      <div id="apicontent">
        <h1>Usage<span><a class="mark" href="#synopsis_usage" id="synopsis_usage">#</a></span></h1>
<!--introduced_in=v0.10.0-->
<!--type=misc-->
<p><code>node [options] [V8 options] [script.js | -e &quot;script&quot; | - ] [arguments]</code></p>
<p>Please see the <a href="cli.html#cli_command_line_options">Command Line Options</a> document for information about
different options and ways to run scripts with Node.js.</p>
<h2>Example<span><a class="mark" href="#synopsis_example" id="synopsis_example">#</a></span></h2>
<p>An example of a <a href="http.html">web server</a> written with Node.js which responds with
<code>&#39;Hello World!&#39;</code>:</p>
<p>Commands displayed in this document are shown starting with <code>$</code> or <code>&gt;</code>
to replicate how they would appear in a user&#39;s terminal.
Do not include the <code>$</code> and <code>&gt;</code> character they are there to
indicate the start of each command.</p>
<p>There are many tutorials and examples that follow this
convention: <code>$</code> or <code>&gt;</code> for commands run as a regular user, and <code>#</code>
for commands that should be executed as an administrator.</p>
<p>Lines that don’t start with <code>$</code> or <code>&gt;</code> character are typically showing
the output of the previous command.</p>
<p>Firstly, make sure to have downloaded and installed Node.js.
See <a href="https://nodejs.org/en/download/package-manager/">this guide</a> for further install information.</p>
<p>Now, create an empty project folder called <code>projects</code>, navigate into it:
Project folder can be named base on user&#39;s current project title but
this example will use <code>projects</code> as the project folder.</p>
<p>Linux and Mac:</p>
<pre><code class="lang-console">$ mkdir ~/projects
$ cd ~/projects
</code></pre>
<p>Windows CMD:</p>
<pre><code class="lang-console">&gt; mkdir %USERPROFILE%\projects
&gt; cd %USERPROFILE%\projects
</code></pre>
<p>Windows PowerShell:</p>
<pre><code class="lang-console">&gt; mkdir $env:USERPROFILE\projects
&gt; cd $env:USERPROFILE\projects
</code></pre>
<p>Next, create a new source file in the <code>projects</code>
 folder and call it <code>hello-world.js</code>.</p>
<p>In Node.js it is considered good style to use
hyphens (<code>-</code>) or underscores (<code>_</code>) to separate
 multiple words in filenames.</p>
<p>Open <code>hello-world.js</code> in any preferred text editor and
paste in the following content.</p>
<pre><code class="lang-js">const http = require(&#39;http&#39;);

const hostname = &#39;127.0.0.1&#39;;
const port = 3000;

const server = http.createServer((req, res) =&gt; {
  res.statusCode = 200;
  res.setHeader(&#39;Content-Type&#39;, &#39;text/plain&#39;);
  res.end(&#39;Hello World!\n&#39;);
});

server.listen(port, hostname, () =&gt; {
  console.log(`Server running at http://${hostname}:${port}/`);
});
</code></pre>
<p>Save the file, go back to the terminal window enter the following command:</p>
<pre><code class="lang-console">$ node hello-world.js
</code></pre>
<p>An output like this should appear in the terminal to indicate Node.js
server is running:</p>
<pre><code class="lang-console"> Server running at http://127.0.0.1:3000/
 `
</code></pre>
<p>Now, open any preferred web browser and visit <code>http://127.0.0.1:3000</code>.</p>
<p>If the browser displays the string <code>Hello, world!</code>, that indicates
the server is working.</p>
<p>Many of the examples in the documentation can be run similarly.</p>

      </div>
    </div>
  </div>
  <script src="assets/sh_main.js"></script>
  <script src="assets/sh_javascript.min.js"></script>
  <script>highlight(undefined, undefined, 'pre');</script>
  <!-- __TRACKING__ -->
</body>
</html>

